Wheat flour is a grain powder formed by milling or grinding wheat grain, or simply “wheat.” Wheat is typically characterized by protein content, and the price of wheat typically correlates to the protein content, with higher protein wheat typically being sold for a higher price. Similarly, wheat flour is also typically characterized and sold by the protein content. During milling, one or more batches of wheat may be blended together to produce a grain powder with a specified protein content, and thus, a particular manufacturing performance. For example, high-protein wheat may be blended with low-protein wheat to produce a grain powder having a protein content between that of the high-protein wheat and the low-protein wheat.
Wheat flour is a main ingredient in a number of commercially available baked products and ready-to-bake dough, such as refrigerated dough and frozen dough products. Producing consistent and high quality dough and baked products, particularly on a commercial scale, is difficult because of variations in wheat and wheat flour. For example, the amount of water and mixing required for a dough (also referred to as mixing characteristics) may vary by protein, wheat species, growing region, growing season (winter or spring), and grain color (red, white or amber).
Protein has historically been one of the specifications correlated to a dough's mixing characteristic(s) and a dough's manufacturing performance and bake quality in large scale food processing. In the baking industry, Farinographs are often used to characterize the properties of wheat flour. A Farinograph measures and records the torque required to mix a water and flour dough sample over time, and provides the results as a curved graph, known as a Farinogram, having a vertical axis labeled in Brabender Units (BU), an arbitrary unit correlating to the apparent viscosity of the sample, and an horizontal axis labeled in time. The Farinogram can be used to determine the performance characteristics of the flour or dough based on the content of wheat gluten or protein. For example, the Farinogram can be used to estimate the mixing requirements for dough development and the amount of water required for the dough. The Farinograph does not provide a perfect characterization of the dough's potential performance, although it is perhaps the most well known correlation.
Standardized conditions for testing flour with a Farinograph are provided in AACC Method No. 54-21.02, entitled Rheological Behavior of Flour by Farinograph: Constant Flour Weight Procedure, and AACC Method No. 54-22.01, entitled Rheological Behavior of Flour by Farinograph: Constant Dough Weight Procedure. The AACC methods require strict control of conditions, including temperature, are time consuming as multiple runs may be required for one flour sample and the accuracy of the results depend on the skill of the technician reading and interpreting the Farinogram.